Catalysts for the curing of a water-curable isocyanate-functional prepolymer

ABSTRACT

New catalysts useful in the curing of a water-curable isocyanate-functional prepolymer are provided. The new catalyst is a new 2,2&#39;-dimorpholinyldialkyl ether. The use of the improved catalyst provides prepolymer/catalyst premix compositions having equivalent or increased shelf stability and which, when water-cured, yield resins having superior early strenghts. A method of curing an isocyanate-functional prepolymer and articles useful as orthopedic bandages are also provided.

This application is a division of application Ser. No. 784,344, filedOct. 4, 1985, now U.S. Pat. No. 4,705,840.

FIELD OF THE INVENTION

This invention relates to new catalysts for the curing of awater-curable isocyanate-functional prepolymer. More particularly, thisinvention relates to new 2,2'-dimorpholinyldialkyl ethers and their useas catalysts in the curing of water-curable isocyanate-functionalprepolymers.

BACKGROUND OF THE INVENTION

Orthopedic casts for use in the treatment of bone fractures or otherconditions requiring immobilization of the body member are generallyformed from a sheet of fabric or scrim material impregnated with asubstance which hardens into a rigid structure after the sheet has beenwrapped around the body member.

The orthopedic casts now most commonly used are comprised of afiberglass scrim impregnated with a water-curable isocyanate-functionalprepolymer. These casts when cured have a higher strength to weightratio than plaster-of-paris, are impervious to water and provideexcellent radiolucency. U.S. Pat. No. 4,411,262 (von Bonin) and U.S.Pat. No. 4,502,479 (Garwood) disclose water-curableisocyanate-functional prepolymers useful orthopedic bandages.

The prepolymer typically includes a tertiary amine catalyst in an amountselected to optimize curing time. After the resin-impregnated scrim hasbeen immersed in water, sufficient "working time", e.g., 3 to 5 minutes,should be provided in which the wrapping is accomplished and the cast ismanually molded into shape. However, after the cast is shaped, the resinshould harden rapidly, typically in 15-30 minutes and preferably less,into a rigid, high-strength, weight-bearing cast.

U.S. Pat. No. 4,376,438 (Straube et al.) discloses an orthopedic castingmaterial wherein the tertiary amine catalyst is chemically linked to thepolymer portion of the isocyanate functional prepolymer. No separatecatalyst is required.

U.S. Pat. No. 4,502,479 (Garwood et al.) discloses the use of tertiaryalkanolamines, e.g., dimethylethanolamine and dimethylaminodiethylether, as catalysts in the curing of a water-curable isocyanatefunctional prepolymer. At concentrations which do not adversely affectshelf stability, these simple catalysts do not cure as fast as desiredby many experienced cast appliers.

U.S. Pat. No. 4,433,580 (Yoon) discloses the use of2,2'-dimorpholinyldiethyl ether (DMDEE) as a catalyst in the cure of awater-curable isocyanate-functional prepolymer on an open-weave fibroussubstrate to form an orthopedic bandage. The use of DMDEE is said toprovide an orthopedic bandage having increased shelf-stability andacceptable set time.

Commercially available orthopedic bandages containing DMDEE typicallycontain about 2-3 percent by weight DMDEE (about 7.5-10 mole percent).These commercially available orthopedic bandages, while havingacceptable shelf stability and set time, do not exhibit superior earlystrengths. Superior early strengths are particularly advantageous in thecase of leg casts which must be weight bearing in a relatively shorttime after application to permit the patient to ambulate.

A journal article, H. Igarishi, et al., "On the Synthesis andPharmacology of Basic-sec, tert-Alcohol and Derivatives", YakugakuZasshi, 93, 554, 563-564 (1973) discloses the preparation of a mixtureof 1-methyl-2-N-morpholinoethyl 2'-morpholinoethyl ether dihydrochlorideand 2-methyl-2-N-morpholinoethyl 2'-morpholinoethyl etherdihydrochloride and a mixture of di(1-methyl-2-N-morpholinoethyl) etherdihydrochloride and 2-methyl-2-N-morpholinoethyl2'-methyl-2'-N-morpholinoethyl ether dihydrochloride and thepharmacological, e.g., antispasmodic and analgesic, activities of therespective mixtures.

SUMMARY OF THE INVENTION

This invention relates to a composition useful as a catalyst in thecuring of a water-curable isocyanate-functional prepolymer resincomprising a substantially pure amino ether compound having thestructural formula: ##STR1## wherein:

each of are individually hydrogen or lower alkyl; and

R⁹ is a methyl group or a phenyl group wherein the phenyl group may haveone or more lower alkyl substituents.

As used herein, the term lower alkyl shall refer to alkyl groups havingfrom about 1 to about 4 aliphatic carbon atoms. The term "substantiallypure" shall mean (a) a homogeneous physical phase having less than 50percent by weight of an organic solvent for the amino ether compoundpreferably less than 10%, most preferably less than 1%, and/or (b)substantially isomerically pure, i.e., having less than 25 percent byweight of a position isomer of the amino ether compound, preferably less10 percent. This invention also relates to a method of catalyzing thecuring of a water-curable isocyanate-functional prepolymer resincomprising forming a mixture of:

(a) water-curable isocyanate-functional prepolymer resin,

(b) water, and

(c) a catalytically effective amount of an amino ether compound havingthe above structural formula.

This invention also relates to a composition comprising an amino ethercatalyst as described above and an isocyanate-functional prepolymerresin. These compositions are useful as adhesives, coatings and sealantsand as the reinforcing resin for an orthopedic bandage. This inventionalso relates to an article comprised of a flexible sheet in contact withthe above-described catalyst/resin composition. This invention alsorelates to a method of orthopedic casting using the above-describedarticle.

It has been found that the use of the amino ether compounds having theabove structural formula yield water-curable resin compositions havingequivalent or better shelf stability and, when cured, yield resinshaving superior early strengths compared to the identical resinsprepared with the same concentration of a catalyst of the prior art.

DETAILED DESCRIPTION OF THE INVENTION

The amino ether catalysts of this invention are2,2'-dimorpholinyldialkyl ethers having the structural formula describedabove. The preparation of the amino ether compounds described above maybe accomplished by the following reaction: ##STR2## wherein R¹ -R⁹ areas previously described, M is an alkali or alkaline earth metal atom(e.g., Na or Ca), and X is a halogen atom (e.g., Cl). The above reactionis a variation of the type reaction known in the art as a Williamsonether synthesis. Such a reaction is conveniently conducted by dissolvingan appropriate alcohol in an inert solvent (e.g., an aromatichydrocarbon) and forming a corresponding alkoxide by the addition of analkali metal (e.g., sodium) or sufficiently alkaline form thereof (e.g.,hydride, oxide, etc.) and application of heat. The resulting alkoxide isthen reacted with an appropriate alkyl halide, usually by dropwiseaddition of the alkyl halide to the alkoxide, to form the desired ethercompound. The desired amino ether compounds can be isolated directlyfrom the reaction mixture or the reaction mixture can be acidified toisolate the amino ether as an acid salt. It is believed that the saltmust be neutralized at least partially to obtain a free aminefunctionality before the amino ether compound can be used as a catalystas described hereinafter.

Representative compounds of this invention include:

4-[2-[1-methyl-2-(4-morpholinyl)ethoxy]-ethyl]-morpholine;

4-[2-[2-(4-morpholinyl)-1-methylethoxy]-ethyl]-2,6-diisopropylmorpholine;

4-[2-[-(4-(2,6-dibutylmorpholinyl))-1-methylethoxy]-ethyl]-2,6-dibutylmorpholine;

4-[2-[1-phenyl-2-(4-morpholinyl)ethoxy]-ethyl]-2-methylmorpholine;

4-[2-[1-methyl-2-(3-methyl-4-morpholinyl)-ethoxy]-ethyl]-morpholine;

4-[2-[1-methyl-2-(2-methyl-4-morpholinyl)-ethoxy]-ethyl]-morpholine;

4-[2-[2-(4-morpholinyl)propoxy]-ethyl]-3-methylmorpholine;

4-[2-[2-(4-morpholinyl)propoxy]-ethyl]-2-methylmorpholine;

4-[2-[2-(4-(3-methylmorpholinyl))-1-methylethoxy]-ethyl]-3-methylmorpholine;

4-[2-[2-(4-(3-methylmorpholinyl))-1-methylethoxy]-ethyl]-2-methylmorpholine;

4-[2-[2-(4-(2-methylmorpholinyl))-1-methylethoxy]-ethyl]-2-methylmorpholine.

The preferred compounds are those wherein R⁹ is methyl or phenyl and areindividually hydrogen or methyl, e.g.,4-[2-[-methyl-2-(4-morpholinyl)ethoxy]ethyl]morpholine (hereinafterreferred to as MEMPE).

The term "substantially pure" shall mean (a) a homogeneous physicalphase having less than 50 percent by weight of an organic solvent forthe amino ether compound preferably less than 10%, most preferably lessthan 1%, and/or (b) substantially isomerically pure, i.e., having lessthan 25 percent by weight of a position isomer of the amino ethercompound, preferably less 10 percent. For example, the journal articleby Igarishi discloses a method of preparing the dihydrochloride salts ofamino ether compounds. That method of preparing this amino etherdihydrochloride involves the generation of corresponding free amines ina solution of an organic solvent for the amino ethers, e.g., diethylether. Accordingly, Igarishi does not disclose an amino ether compoundwhich is substantially unsolvated.

Further, Igarishi purports to disclose the preparation of1-methyl-2-N-morpholinylethyl 2'-N-morpholinylethyl etherdihydrochloride. Igarishi discloses that this compound is prepared byreacting the alkoxide of 2-morpholine-1-ethanol with1-morpholine-2-chloropropane. However, 1-morpholine-2-chloropropaneexists, in solution, in equilibrium with an ionic isomer as shown below.##STR3## Because the alkoxide of 2-morpholine-1-ethanol can react withthe ionic isomer at either of the isopropyl carbon atoms bonded tonitrogen, the reaction produces a solution mixture containing2-methyl-2-N-morpholinylethyl 2'-morpholinylethyl as well as the desired1-methyl-2-N-morpholinylethyl 2'-morpholinylethyl ether. Accordingly,the method disclosed by Igarishi cannot be used to prepare1-methyl-2-N-morpholinylethyl 2'-morpholinylethyl ether substantiallyfree from its position isomer without the use of laborious techniques toseparate a mixture of the isomers. In contrast, the method of thisinvention employs reactants which do not yield a mixture of positionisomers such that the method of this invention can be used to obtainamino ether compounds which are substantially isomerically pure.

The water-curable isocyanate-functional prepolymers useful in thepresent invention are known in the art. They are generally prepared byreacting a polyol with an excess of a polyisocyanate.

It is preferred to use an isocyanate which has low volatility such asdiphenylmethane diisocyanate (MDI) rather than a more volatile materialsuch as toluene diisocyanate (TDI). Suitable isocyanates include2,4-toluene diisocyanate, 2,6-toluene diisocyanate, mixtures of theseisomers, 2,4'-diphenylmethane diisocyanate, 1,4'-diphenylmethanediisocyanate, mixtures of these isomers together with possible smallquantities of 2,2'-diphenylmethane diisocyanate (typical of commerciallyavailable diphenylmethane diisocyanate), and aromatic polyisocyanatesand their mixtures such as are derived from phosgenation of thecondensation product of aniline and formaldehyde.

4,4'-Diphenylmethane diisocyanate is commonly known as "methylenediisocyanate" or "MDI". In its pure form MDI is commercially availableas Isonate™ 125M from the Upjohn Co., and as Mondur™ or Multrathane™ Mfrom Mobay Chemical Corp. As used herein "isocyanate-functionalderivatives of MDI" will be construed to include isocyanates actuallyprepared from MDI, and will also include isocyanates which have notactually been prepared from MDI but which have chemical structurescapable of being prepared from MDI if desired. Isocyanate-functionalderivatives of MDI which can be used in this invention include liquidmixtures of MDI and melting point modifiers (e.g., mixtures of MDI withpolycarbodiimide adducts such as Isonate™ 143L, commercially availablefrom the Upjohn Co., and Mondur™ CD, commercially available from MobayChemical Corp., and Rubinate™ M, commercially available from RubiconChemicals, Inc.) and blocked isocyanate compounds formed by reacting MDIor the above-described isocyanate-functional derivatives of MDI withblocking agents such as ketoximes, phenols, and the like. Such blockedisocyanate compounds will, for convenience, be regarded herein asisocyanate-function derivatives will sometimes be referred tocollectively herein as "MDI".

Typical polyols for use in the prepolymer system include polypropyleneether glycols and polyols (available from Union Carbide under thetradename Niax Polyol and from BASF Wyandotte under the tradenamePluracol™), polytetramethylene ether glycols (Polymeg™ from the QuakerOats Co.), polycaprolactone polyols (Niax™ PCP series of polyols fromUnion Carbide), and polyester polyols (hydroxyl terminated polyestersobtained from esterification of dicarboxylic acids and diols such as theRucoflex™ polyols available from Ruco division, Hooker Chemicals Co.).

The isocyanates and the polyols are reacted with one another underconventional polyurethane reaction conditions known to those skilled inthe art. Preferably the NCO:OH ratio of the reactants is about 1.2:1 to4.5:1, and most preferably is about 1.8:1 to 3.8:1. As the NCO:OH ratiois increased, the compositions of the invention tend to be less moisturesensitive and to have longer shelf life. Ordinarily, the prepolymer isprepared under a suitable atmosphere (e.g., nitrogen). It is convenientto add MDI to the reaction vessel first, followed by heating or additionof solvent if necessary to liquefy the MDI, followed by addition ofpolyols. Reactants which are in solid form are dissolved in a suitablesolvent or melted prior to addition of the other reactants. The reactionmixture is maintained at about 50° C. to 70° C. until the desiredisocyanate equivalent weight is obtained. The prepolymer can beseparately stored for later use or any remaining ingredients of thecompositions of the invention can be added to the reaction vessel.

As one example of an alternate method for preparation of prepolymers(e.g., prepolymers with a polyether backbone) used in this invention,one mole of a polytetramethylene oxide diol and containing about 2 moleof reactive hydroxyl groups is reacted with excess (i.e., more than 2moles) phosgene in the presence of a low boiling alkylamine, (e.g.,(CH₃)₃ N) at about 0° C. in a closed reaction vessel to provide adi(carbamoyl chloride)-terminated polyether. This compound reacted withabout 2.2 moles di(para-aminophenyl)methane in the presence of about 2.2moles low boiling alkylamine to provide a di(amine)-terminated polyetherpolyurethane. This compound is reacted with excess phosgene in thepresence of low boiling alkylamine at about 0° C. in a closed containerto provide the desired prepolymer.

Regardless of the method of preparation of the prepolymer, the freeisocyanate groups of the prepolymer can, if desired, be blocked todecrease moisture sensitivity, e.g., by reacting the prepolymer with alabile reagent that can be displaced during the subsequent curing of theprepolymer. Suitable blocking agents preferably do not require heat fordeblocking, and include di(lower alkyl)malonates, ethyl acetoactate,isophorone, acetone, methyl ethyl ketone, and the like. Ordinarily, anexcess of blocking agent is employed to assure that all free isocyanatesgroups of the prepolymer react with the blocking agent. It has beenfound that the compositions of the present invention are sufficientlystable that the use of a blocking agent is not ordinarily required.Elimination of the blocking agent can reduce cost and reduce theevolution of volatile substances during cure. Preferably, no blockingagents are employed in the composition of this invention.

The prepolymer should be stored until use in a container that is bothmoisture and oxygen impermeable to increase the shelf-life of theprepolymer. During storage the contact of the prepolymer with oxygen andmoisture is accordingly minimized.

The prepolymer and amino ether catalyst are mixed using conventionalmixing techniques. As with any storage of the prepolymer, the mixingshould be done under anhydrous conditions, preferably in substantiallyinert atmosphere, e.g., nitrogen gas. The resulting prepolymer/catalystmixture should also be stored under anhydrous conditions in a containersubstantially impermeable with respect to oxygen and moisture.

The prepolymer/catalyst compositions have properties which allow utilityin a variety of applications including use as an adhesive, a coating, asealant, a structural reinforcing resin, etc. When used as an adhesive,the composition is placed between an article and a substrate, in contactwith both, and exposed to moisture sufficient to cure the resin. Whenused as a coating, the composition is deposited as a continuous layer onthe surface of the article to be coated and exposed to moisturesufficient to cure the resin. When used as a sealant, the composition isdeposited in the void to be sealed and exposed to moisture sufficient tocure the composition. When used as a structural reinforcing resin, thecomposition is coated onto and/or impregnated into an article comprisedof a flexible sheet of fibrous or non-fibrous fabrics, papers, felts,foams and the like and exposed to moisture sufficient to cure thecomposition. The compositions are particularly useful when applied toporous flexible sheets which can then be exposed to moisture to formhardened orthopedic bandages.

Orthopedic Bandages and Other Sheet Material Articles

One of the most advantageous uses of the prepolymer/catalyst compositionof this invention is the use of the composition as a coating for aflexible sheet, which coating hardens on exposure to moisture.

An especially preferred resin for use in the casting material of theinvention uses an isocyanate known as Isonate™ 143L available from theUpjohn Company (a mixture containing about 73% of MDI) and apolypropylene oxide polyol available from Union Carbide as Niax™ PPG725. To prolong the shelf-life of the material, it is preferred toinclude about 0.02-0.1 percent by weight of benzoyl chloride or othersuitable stabilizer.

The reactivity of an isocyanate-functional prepolymer once it is exposedto water as a curing agent is controlled by the amino ether catalystsdescribed above. An effective amount of the amino ether compound is theamount necessary to achieve the desired degree of reactivity.

The reactivity must not be so great that: (1) a hard film quickly formson the resin surface preventing further penetration of the water intothe bulk of the resin; or (2) the cast becomes rigid before theapplication and shaping is complete. The precise amount of amino ethercatalyst will depend upon the nature of the isocyanatefunctionalprepolymer, but will generally range from about 0.1% to about 5% byweight of the isocyanate-functional prepolymer, preferably from about0.1 to about 3%, most preferably from about 1.0 to about 2%.

Foaming of the resin should be minimized since it reduces the porosityof the cast and its overall strength. Foaming occurs because carbondioxide is released when water reacts with isocyanate groups. One way tominimize foaming is to reduce the concentration of isocyanate groups inthe prepolymer. However, in order to have reactivity, workability,shelf-life and ultimate strength, an adequate concentration ofisocyanate groups is necessary. Although foaming is less at low resincontents, adequate resin content is required for desirable castcharacteristics such as strength and resistance to peeling. It has beenfound that the most satisfactory method of minimizing foaming is to adda foam suppressor such as silicone Antifoam A (Dow Corning), DB-100silicone fluid (Dow Corning), or silicone surfactants L550 or L5303(Union Carbide) to the resin. It . is preferred to use a silicone liquidsuch as Dow Corning DB-100 at a concentration of about 0.1 to 1.0percent by weight.

The sheet material articles of this invention, useful as orthopedicbandages, are preferably prepared by mixing an isocyanate-functionalprepolymer with an ether catalyst as described above and coating theresulting premix onto a flexible sheet, e.g., a fabric. The sheetmaterial articles of this invention may also be used outside the fieldof orthopedic bandages, i.e., wherever a fabric reinforced sheet ofwater-cured resin is useful, e.g., in repairing a variety of structuressuch as repairing a breach in a cable jacket or conduit.

In the preferred embodiments relating to sheet materials, a porous,flexible sheet material will be impregnated with the composition. Apreferred example of a porous, flexible sheet material which may beimpregnated with the compositions of this invention is disclosed in U.S.Pat. No. 4,502,479, incorporated herein by reference thereto. The fabrictherein is stated to impart high structural strength to an orthopedicbandage prepared therefrom.

A particularly preferred fabric for use in the orthopedic bandages ofthis invention is disclosed in U.S. application Ser. No. 668,881, filedNov. 6, 1984, the disclosure of which is incorporated herein byreference thereto. This fabric is used in the orthopedic bandageavailable from 3M as Scotchcast™ 2 Casting Tape. The fabric is afiberglass fabric comprised of extensible knit fiberglass which exhibitsan extensibility of at least about 20% in the length direction and hasbeen set to reduce fraying.

The fabric used in the casting material is generally formed in rolls ofvarious widths, generally from one inch to six inches wide. The fabricis impregnated with the curable resin material in an amount, in terms ofvolume, of from one to three times the volume of the material formingthe fabric, and in the preferred embodiment employing a fiberglassfabric of from 40% to 50% by weight of the impregnated casting material.The term "impregnate" is used to describe the condition in which thepolymer is thoroughly intermingled with and in surrounding relation tothe threads of fibers of the fabric and does not necessarily indicatethat the resin is to any extent absorbed by the fibers themselves.Generally, the resin solution will flow into the capillary spacesbetween contiguous filaments of the fabric and will become rigidlybonded to the fabric upon curing.

The amount of resinous component applied to the fabric for an orthopedicbandage must be sufficient for the formation of a strong interlayerlaminate bond but not so much as to occlude the porosity andunnecessarily thicken the resin film which should be thin for rapid andcomplete hardening. Excessive resinous component may also cause thecasting tape to be messy to handle because of stickiness or dripping andtransfer of resin.

The resin coated tape may be in the form of a roll wound up on a plasticcore sealed within a moisture and oxygen impermeable container. For use,the container is opened and the roll is fully immersed in tap water forabout 5 to 30 seconds. This is sufficient time for water to seep intothe porous material and displace air. As long as the resin content isnot too high to cause the openings in the fabric to be filled withresin, more than enough water is absorbed by the roll in this manner.The roll may be squeezed underwater to replace entrapped air with water.When the roll is unwound during wrapping of the cast, the excessmoisture coats freshly exposed resin surfaces insuring thorough wettingand rapid hardening of the cast. An alternate method comprises wrappingthe cast without dipping and then allowing atmospheric moisture or waterprovided by spraying or by application of a wet towel to cure theprepolymer.

Prior to applying the orthopedic cast, protective padding is positionedabout the limb or body member of the patient. The padding may take theform of a tubular stockinet or some other convenient form such as forexample an elongated strip or bandage which may be wrapped about thebody member.

With the padding in a proper position, the moistened orthopedic castmaterial is wrapped about the body member and over the protectivepadding in a manner similar to the application of an elastic-typebandage. The cast is shaped in a manner similar to the shaping of aplaster-of-paris cast.

Eight or fewer layers of the cast material should be sufficient to forma cast having weight-bearing strength within 30 minutes, i.e., acylindrical laminate having eight or fewer layers should support 20pounds of pressure per inch of cylinder length, and significant strengthshould develop within 71/2 minutes. The tests to determine thesestrengths are discussed more fully below.

Adhesives, Coatings and Sealants

The compositions of this invention comprised of the isocyanatefunctional prepolymer resin and the amino ether compounds of thisinvention will be useful in a variety of applications whereinisocyanate-functional prepolymers have been used previously, i.e., assealants (e.g. caulks), coatings, adhesives, etc., as well as areinforcing resin for an orthopedic bandage.

In addition to the polyols described above as useful in preparing anisocyanate-functional prepolymer, polyols having primary hydroxyl groupsas disclosed in U.S. Pat. No. 4,511,626, the entire disclosure of whichis incorporated herein by reference thereto, are especially useful.

As used herein, a "primary hydroxyl group" is a monovalent radicalhaving a hydroxyl radical bonded to a methylene radical. Similarly,"secondary hydroxyl group" will be used herein to refer to a monovalentradical having a hydroxyl radical bonded to a methylidyne radical. Asused herein, a "primary polyol" is a polyol containing two or moreprimary hydroxyl groups. Similarly, "secondary polyol" will be usedherein to refer to polyols containing two or more secondary hydroxylgroups. Polyols containing both primary hydroxyl groups and secondaryhydroxyl groups will be regarded herein as primary polyols if theprimary hydroxyl groups thereof are reactive with MDI.

Suitable primary polyols have a backbone containing, for example,aliphatic, olefinic, ether, ester, thioether, urethane or urea linkages.Primary polyols containing ether linkages (e.g., those having apolyether backbone) are preferred. The primary polyols have a numberaverage molecular weight between about 90 and 8000, most preferablybetween about 200 and 3000. The primary polyols preferably have 2 to 4primary hydroxyl groups per molecule. Expressed in terms of hydroxylequivalent weights, the primary polyols preferably have a hydroxylequivalent weight between about 45 and 2500, most preferably betweenabout 100 and 1500. "Hydroxyl number", as used herein, refers to thenumber of milligrams of KOH having the same hydroxyl content as one gramof the polyol. "Hydroxyl equivalent", as used herein, refers to thequotient obtained by dividing the number average molecular weight of thepolyol by the number of hydroxyl groups therein. "NCO equivalent", asused herein refers to the quotient obtained by dividing the numberaverage molecular weight of an isocyanate by the number of reactiveisocyanate groups therein.

Suitable primary polyols for use in this invention includepolytetramethylene oxide glycols, ethylene oxide-terminatedpolypropylene glycols, polyethylene glycols, hydroxyl-terminatedpolybutadienes, aliphatic glycols, polyester polyols (e.g., polyacrylatepolyols or polycaprolactone polyols), fatty alcohols, and triglycerides(e.g., castor oil). Mixtures of primary polyols can be used if desired.

Suitable commercially available primary polyols include Pluracol™ TPE4542 ethylene oxide-terminated polypropylene glycol, commerciallyavailable from BASF/Wyandotte Corp., Voranol™ E series polyethyleneglycols, commercially available from Dow Chemical Co., QO Polymeg™ 650,1000, or 2000 series polytetramethylene oxide glycols, commerciallyavailable from Quaker Oats, Co., Teracol™ 2000 polytetramethyleneoxideglycol, commercially available from E. I. duPont de Nemours & Co., Inc.,Niax™ series PCP™, and Capped Polyols™, as well as Polymer Polyols™ and"Mixed Oxide Polyols" containing primary hydroxyl groups, commerciallyavailable from Union Carbide Corp., Poly-G™ 53-, 55-, 56-, 85-, and 86-series ethylene oxide terminated polypropylene glycols, commerciallyavailable from Olin Chemicals, Poly bd™ hydroxyl-terminatedpolybutadienes, commercially available from ARCO/Chemical Co., andMultron™ and Multrathane™ polyester polyols, commercially available fromMobay Chemical Co.

A preferred subclass of primary polyols for use in this invention arepolytetramethylene oxide glycols, particularly those having a numberaverage molecular weight from about 650 to 2000, preferably from about1000 to 2000. Another preferred subclass of primary polyols for use inthis invention are ethylene oxide-terminated polypropylene glycols,particularly those having a number average molecular weight from about500 to 3000, preferably from about 1000 to 2000. A third preferredsubclass of primary polyols for use in this invention arepolycaprolactone polyols, particularly those having a number averagemolecular weight from about 300 to 3000, preferably about 800 to 2000.

For optimum shelf life in the compositions of this invention, it ispreferred that the primary polyol(s) have a pH between about 5.5 and 7.Most preferably, the pH of the primary polyols is between about 6 and6.5.

If desired, the prepolymers used in this invention can be derived fromreaction mixtures containing MDI and primary polyols together withadditional reactants such as aromatic isocyanates (e.g., 2,4-toluenediisocyanate, hereafter referred to as "TDI"), secondary polyols, orother additional reactants which do not materially detract from thefunctioning of the prepolymer in the compositions of this invention. Forexample, it is frequently desirable to employ secondary polyols in thereaction mixture from which the prepolymers are prepared, in order toadjust the handling properties, physical properties, or curecharacteristics of the compositions of the invention. Preferably, thepolyols in the prepolymer reaction mixture are about 25 to 100 weightpercent primary polyols and 0 to 75 weight percent secondary polyols,and most preferably about 40 to 80 weight percent primary polyols and 20to 60 weight percent secondary polyols. Suitable secondary polyolsinclude polypropylene ether diols and higher polyalkylene ether diols(e.g., polybutylene ether diols), polyalkylene ether triols (e.g., thoseprepared by condensing a lower alkylene oxide such as ethylene oxide orpropylene oxide with an alkylene triol such as glycerine,trimethylopropane, or the like), and polyols with tetra- or higherfunctionality such as pentaerythritol, sorbitol, and the like.

Preferred secondary polyols include propylene oxide-terminated ethyleneoxide glycols and polypropylene glycols. Suitable commercially availablesecondary polyols which can be incorporated into prepolymers for use inthis invention include Niax™ series "PPG", "LG", "LHT", and "SpecialPurpose Polyols" containing secondary hydroxyl groups, commerciallyavailable from Union Carbide Corp., Pluracol™ series polyols containingsecondary hydroxyl groups, commercially available from BASF/WyandotteCorp., Voranol P™ series polypropylene glycols, commercially availablefrom Dow Chemical Co., and Poly-G™ 20- and 30-series polypropyleneglycols, commercially available from Olin Chemicals.

As used herein, an "effective amount" of an ingredient is an amountsufficient to provide desired physical properties (e.g., cure rate ortensile strength) in the compositions of the invention. An effectiveamount of amino ether compound preferably is about 0.002 to 2 weightpercent, and most preferably about 0.05 to 0.5 weight percent based uponthe weight of prepolymer.

The prepolymer and amino ether are mixed using conventional mixingtechniques. Preferably the amino ether is dissolved in a suitablesolvent (e.g., toluene) and added to the prepolymer. The resultingmixture should be stored in a sealed container until the time of use.

The mixture of prepolymer and amino ether can contain other ingredientsor adjuvants if desired. It is also preferred to include an effectiveamount of other adjuvants such as extender and/or reinforcing fillers(e.g., carbon black, metal oxides such as zinc oxide, and minerals suchas talc, clays, silica, silicates, and the like) in the compositions ofthe invention. Carbon black is a particularly preferred filler for usewhere resistance to degradation caused by ultraviolet light exposure isdesired, e.g., for use in windshield sealants. An effective amount offiller preferably is between about 0 and 80 weight percent based uponthe weight of prepolymer and most preferably between about 20 and 60weight percent.

Solvents such as toluene, xylene, methyl ethyl ketone, acetone, ethylacetate, Cellosolve™ Acetate (commercially available from Union CarbideCorp.), and other suitable materials free of isocyanate-reactivemoieties can be employed in these compositions of this invention.Toluene is a preferred solvent. An effective amount of solventpreferably is between about 0 and 80 weight percent based upon theweight of prepolymer.

Plasticizers such as partially hydrogenated terphenyls (e.g., "HB-40",commercially available from Monsanto Corp.), dioctyl phthalate, dibutylphthalate, diisodecyl phthalate, or tricresyl phosphate can also beemployed in these compositions of this invention. Partially hydrogenatedterphenyls are a preferred plasticizer. An effective amount ofplasticizer preferably is between about 0 and 25 weight percent basedupon the weight of prepolymer.

In addition, the compositions of the invention can contain antioxidants,pigments, UV absorbers, adhesion promoters, drying agents (e.g.,molecular sieves such as sodium aluminum silicate or dessicants such aszeolite, silica gel, barium oxide, or calcium oxide), and the like.

For use in glass sealant compositions, it is desirable to employ aneffective amount of a silane-containing primer, either as an ingredientof the sealant composition, or as a separate layer placed between thesurface of the glass to be sealed and the layer of sealant, or as bothan ingredient of the sealant composition and as a separate layer.Suitable silane-containing primers are described in U.S. Pat. Nos.3,627,722 and 3,707,521. If silane-containing primer is incorporatedinto a sealant composition of this invention, an effective amount ofsilane-containing primer preferably is between about 2.5 and 10 weightpercent, based upon the weight of prepolymer. If silane-containingprimer is employed as a separate primer coating, then an effectiveamount of such silane-containing primer in the primer coating will be anamount which gives the desirous degree of bonding performance given themode of application of the primer layer and the sealant composition tothe surfaces which are to be bonded.

A particularly preferred prepolymer/catalyst composition for use as anadhesive coating or sealant will also contain an effective amount of aterpene-phenolic resin in addition to the silane described above. Thecompositions have excellent adhesion to unprimed metal, glass andconcrete even when exposed to moisture or ultraviolet radiation. Thesecompositions are more particularly described in U.S. application Ser.No. 697,831, filed Feb. 4, 1985, now U.S. Pat. No. 4,539,345.

The compositions of the invention can be put up in packages inaccordance with techniques known to those skilled in the art. Suitablepackages include, for example, caulking tubes (made, for example, ofpaper, metal, or plastic), screw-capped squeezable tubes, cans, drums,and the like.

The compositions of the invention are cured by exposure to water, e.g.,water vapor or moisture. Ordinary ambient humidity is usually adequateto promote cure. Heat or high humidity will accelerate cure, and lowtemperatures (e.g., 5° C. or less) or low humidity (e.g., 15% R.H. orless) will retard cure. Bonds to damp substrates (e.g., wood) typicallycure faster than bonds to dry substrates (e.g., glass).

The compositions of the invention can be employed in any applicationwhere a high-performance, rapidly-curing adhesive, coating, or sealantis desired. One such use includes the bonding of glass (e.g.,windshields and backlights) to vehicles, either at the time of originalmanufacture or at the time of glass replacement, in vehicles such asautomobiles, trucks, aircraft, trains, and the like. When so used, thecompositions of the invention provide rapid drive-away times followingglass installation. Other uses include building construction (e.g., as astructural adhesive, panel adhesive, moisture barrier, or glazingsealant), assembly line manufacturing (e.g., for assembly of parts byadhesive bonding), and coatings (e.g., deck coatings or roof membranes).The compositions of the invention can be applied to a variety ofarticles and substrates, such as articles or substrates of glass, metal,plastic, wood, leather, masonry, textiles, and the like.

EXAMPLES Examples 1-5 Preparation of Catalysts for Orthopedic BandagesExample 1 4 ethyl-2-(4-morpholinyl)ethoxy]-ethyl]-morpholine

An amount, 871.2 grams, of morpholine (10 moles) and 580.8 grams ofpropylene oxide (10 moles) were mixed in a 2 liter flask and set asidefor seven days at room temperature. At the end of this time, thesolution was distilled under vacuum to give 1396.0 grams (96.1%) ofN-(2-hydroxypropyl)-morpholine as a colorless oil, bp 63°-65° C. at 0.25mm of Hg. Gas chromatographic analysis of the product showed thepresence of only one compound which indicated no position isomer wasformed. The identity of the product was confirmed by elemental analysis,calc. 57.9 C, 10.4 H, 9.65 N; found 57.5 C, 10.3 H, 9.5 N.

One liter of dry toluene was placed in a five liter three necked roundbottom flask equipped with a condensor, nitrogen inlet, overheadstirring motor and an additional funnel. The system was flushed with drynitrogen for five minutes. 115.0 grams of clean sodium metal (5 moles)was cut into pieces and added to the toluene. The toluene was heated toreflux whereupon the sodium melted. Moderate agitation was required toform small droplets of the metal, which facilitated reaction with thealcohol. 726.0 grams of N-(2-hydroxypropyl)morpholine (5 moles) preparedabove was added dropwise to the flask by means of the addition funnel. Amoderate exothermic reaction ensued. After addition of the alcohol wascompleted, the reaction was stirred at reflux overnight.

A solution of N-chloroethyl morpholine in toluene was prepared in thefollowing manner. 930.4 grams of N-chloroethyl morpholine hydrochloride(5 moles) available commercially from Aldrich Chemical Co. was dissolvedin 500 milliliters water. A solution of 300.0 grams of sodium hydroxidein 300 milliliters water was slowly added to the hydrochloride solutionkeeping the temperature below 35° C. during addition. After all thehydroxide solution had been added, the reaction was allowed to stir atroom temperature for five minutes and then transferred to a separatoryfunnel. The upper layer was separated and the bottom layer was washedwith 500 milliliters toluene. The combined organic layers were driedwith anhydrous potassium carbonate, filtered and added in a slow streamto the refluxing alkoxide solution prepared above. After addition thereaction was refluxed overnight.

The reaction was cooled to room temperature and 250 milliliters of waterwere added. The solution was filtered and toluene was removed bydistillation under reduced pressure. The residue was distilled underhi-vacuum to yield 875 grams (67.7%) of catalyst as a pale yellow oil,bp 118°-119° C. at 0.3 mm of Hg. The presence of one compound wasindicated by GC analysis and the structure confirmed as that of thetitle compound by proton NMR and carbon-13 NMR and elemental analysis,calc. 60.4 C, 10.1 H, 10.9 N; found 60.0 C, 9.8 H, 10.8 N.

An amount, 2500.0 grams, of Isonate 143L (modified diphenylmethanediisocyanate) was added to a five liter three-necked round bottom flaskequipped with a thermometer, stirrer and nitrogen inlet. To this wasadded 80.2 grams of the above catalyst (corresponding to an amountequivalent to 5 moles of tertiary amine per 100 moles of the free NCOgroups, i.e., 5 mole %), 4.2 grams of benzoyl chloride and 10.0 grams ofDow-corning DB-100. This was followed by the addition of 221.0 grams ofa 10% solution of BHT (2,6-di-tert-butyl-4-methylphenol) in PPG-725 thenby 1781.8 grams of PPG-725. The equivalent ratio of NCO to OH was 3.5:1.The addition of the polyol was made through a dropping funnel over aperiod of thirty minutes. After addition the polymerization reaction wascarried out at 50°-60° C. for one hour.

The prepolymer was machine coated in an atmosphere substantially free ofmoisture on a three inch wide strip of fiberglass fabric to give thetape containing 40% by weight of the resin. It was then cut in 4 yardlengths and packaged in foil pouches for storage and later use andevaluation.

In addition to the strength testing described below, rolled samples ofthe examples were stored in sealed envelopes similar to those used tostore similar commercial items. These sealed samples were subjected toaccelerated aging tests, i.e., held at elevated temperatures and thenunwound in such a manner that the force needed to unwind the rolls couldbe measured. The samples of this invention exhibited commerciallyacceptable aging results which were comparable to, and often superiorto, the comparative samples.

Example 24-[2-[2-(4-(2,6-dimethylmorpholinyl))-1-methylethoxy]-ethyl]-morpholine

The compound 2,6-dimethyl-N-(2-hydroxypropyl) morpholine was prepared bythe method of Example 1 from 100.56 grams 2,6-dimethylmorpholine (0.87moles) and 50.53 grams of propylene oxide (0.87 moles). Distillation ofthe reaction mixture gave 116.1 grams (76.8%) of the alcohol as a paleyellow oil, bp 70°-72° C. at 0.25 mm of Hg. The following elementalanalysis was obtained: calc. 62.4 C, 11.1 H, 8.1 N; found 62.0 C, 10.8H, 8.0 N.

An amount, 398.5 grams, of 2,6-dimethyl-N-(2-hydroxypropyl) morpholine(2.3 moles) was condensed with the free chloroamine obtained from 390.5grams N-chloroethyl morpholine hydrochloride (2.3 moles) as describedabove to give 325.4 grams (55.7%) of the catalyst as a pale yellow oil,bp 122°-124° C. at 0.3 mm of Hg. The structure was confirmed byelemental analysis, calc. 62.9 C, 10.6 H, 9.8 N; found 62.2 C, 10.4 H,9.8 N.

This catalyst was formulated, coated and tested as described in Example1.

Example 34-[2-[2-(4-morpholinyl)-1-methylethoxy]-ethyl]-2,6-dimethylmorpholine

An amount, 437.9 grams, of N-(2-hydroxypropyl)morpholine (3 moles) wascondensed with the free chloroamine obtained from 642.0 gramsN-chloroethyl-2,6-dimethylmorpholine hydrochloride (3.0 moles) asdescribed above to give 554.8 grams (64.7%) of the catalyst, bp122°-124° C. at 0.3 mm of Hg. The structure was confirmed as that of thetitle compound by elemental analysis, calc. 62.9 C, 10.6 H, 9.8 N; found62.8 C, 10.8 H, 9.8.

This catalyst was formulated, coated and tested as described in Example1.

Example 44-[2-[2-(4-(2,6-dimethylmorpholinyl))-1-methylethoxy]-ethyl]-2,6-dimethylmorpholine

An amount, 389.3 grams, of 2,6-dimethyl-N-(2-hydroxypropyl) morpholine(2.25 moles) was condensed with the free chloroamine obtained from 481.5grams N-chloroethyl-2,6-dimethylmorpholine hydrochloride (2.25 moles) asdescribed above to give 415.9 grams (58.8%) of the catalyst, bp127°-129° C. at 0.3 mm of Hg. The structure was confirmed as that of thetitle compound by elemental analysis, calc. 64.9 C, 10.9 H, 8.9 N; found64.4 C, 10.6 H, 8.9 N.

This catalyst was formulated, coated and tested as described in Example1.

Example 5

4-[2-[1-phenyl-2-(4-morpholinyl)ethoxy]-ethyl]-morpholine

N-(2-hydroxy-2-phenethyl) morpholine was prepared by the method ofExample 1 from 213.9 grams morpholine (2.46 moles) 304.1 grams ofstyrene oxide (2.46 moles). Recrystallization of the reaction mixturefrom 2500 ml of ethyl acetate/hexane (1:4) gave the alcohol as acolorless solid, mp 78°-80° C.

An amount, 828.0 grams, of N-(2-hydroxy-2-phenethyl) morpholine (4moles) was condensed with the free chloroamine obtained from 744.3 gramsN-chloroethyl-morpholine hydrochloride (4 moles) as described above togive 626.4 grams (48.9%) of the catalyst, bp 180° C. at 2 mm of Hg. Thestructure was confirmed as that of the title compound by elementalanalysis, calc. 67.5 C, 8.8 H, 8.7 N; found 67.2 c, 9.0 H, 8.7 N.

This catalyst was formulated, coated and tested as described in Example1.

Ring Strength Test Procedure

The following test is used to determine the strength of a 5.8 cm(2-inch) diameter cylindrical ring of a cured orthopedic bandage inaccordance with this invention when compressed at specified test timesafter exposure to water.

A 7.6 cm (3-inch) wide and 101.6 cm (40-inch) long sample of fiberglassscrim impregnated with isocyanate functional prepolymer resin andcatalyst prepared as described in the examples below is used as a testspecimen. The test environment was maintained at 24° C.±1.5° C. and 55percent ±5 percent relative humidity. The tape was maintained in asubstantially water-free environment from its manufacture until testing.

To begin testing, a 5.8 cm (2 inch) diameter mandrel was covered with alength of 5.8 cm (2 inch) diameter stockinette. A roll of the tape wasimmersed in an 27° C.±0.5° C. water bath. After 30 seconds, the tape wasremoved from the water by the ends of the core and gently shaken tominimize dripping. The loose end of the tape was attached to thestockinette and the tape was manually

unwound and cut to a length of approximately 100 cm (40 inches). A 1.65kg (3/4 lb.) weight was attached to the cut end of the tape such thatthe tape and weight dangled freely below the mandrel. Six layers of tapewere then uniformly wound about the mandrel, the excess tape was cutoff, and the end of the tape was generally smoothed with very lightpressure. No single layer of tape extended beyond any of the otherlayers by more than 0.47 cm (3/16 of an inch). The ring was completelywound by 30 seconds after removal of the water bath.

The ring and stockinette were removed from the mandrel just prior to thetime of compression testing. The ring specimen was mounted in aspecially designed compression test fixture. The text fixture wascomprised of two bars, 1.90 cm (3/4 inches) in width 1.27 cm (1/2 inch)thick and 15.2 cm (6 inches) long, fixed 3.81 cm (11/2 inches) apart. Apenetrating bar, of same dimension as the fixed bars, was placed in thejaws of an Instron Model 1122. The ring was deposited on the two fixedbars and the fixture was placed in the Instron such that the seam of thewound roll was 1/8" to 1/4" beyond where the penetrating bar contactedthe test specimen from above. The crosshead setting of the Instron wasset at 2 inches per minute and the full scale load was set toaccommodate the expected compression strength such that the expectedforce to crush approximately 50-60 percent of the full scale load. Theresults of the compression testing when done at different times fordifferent samples are shown in the tables below. The 71/2 min. strengthtest has been found to correlate closely with the clinical set time ofthe casting material.

A series of orthopedic bandages of this invention were prepared andtested as described above. Examples of this invention are indicated by anumeral and comparative examples by a large case letter.

Strength Testing of Examples 1 and 5 and Comparative Examples A-D

Two mono-substituted amino ether compounds of this invention, i.e.,those of Examples 1 and 5 wherein R¹ -R⁸ are hydrogen and R⁹ methyl orphenyl, are shown below in Table I. The use of the compound DMDEE as thecatalyst is shown in Comparative Example A and the use of alkyl groupsother than methyl as R⁹ are shown in Comparative Examples B-D.

                  TABLE I                                                         ______________________________________                                        Strength of Orthopedic Bandages Prepared                                      With Mono-substituted Amino Ether Compounds                                    ##STR4##                                                                            Catalyst Level:                                                               5 mole %         10 mole %                                                    Strength at:                                                           Example  R.sup.9  71/2 min  30 min                                                                              71/2 min                                                                             30 min                               ______________________________________                                        A        H        3.9       18.9  8.9    22.3                                 1        CH.sub.3 8.1       21.3  11.4   24.3                                 B        C.sub.2 H.sub.5                                                                        5.1       18.0  9.2    20.1                                 C        n-C.sub.4 H.sub.9                                                                      4.2       18.0  --     --                                   D        n-C.sub.8 H.sub.17                                                                     4.3       17.3  7.9    18.1                                 5        phenyl   7.0       24.5  10.0   24.8                                 ______________________________________                                    

The results shown in Table I illustrate that the substitution of anamino ether compound at R⁹ with methyl or phenyl yields a catalyst whichin turn yield casts having improved early strengths as shown by thestrengths at 71/2 min.

By comparing the strength at 71/2 min. using 5 mole % of the catalyst ofExample 1 with the strength at 71/2 min using 10 mole % of the prior artcatalyst of Example A, it can be seen that at least one embodiment ofthis invention allows for the use of approximately one-half the amountof catalyst to obtain comparable set time.

Strength Testing of Examples 2-4 and Comparative Examples E-J

Another series of orthopedic bandages was prepared and tested asdescribed above. The amino ether compounds of this invention, shown inExamples 2-4, were substituted in the R⁹ position with methyl and in theR¹, R³, R⁶ and/or R⁸ positions with methyl. The comparable amino ethercompounds wherein R⁹ is hydrogen or ethyl are shown for comparison inComparative Examples E-J.

                                      TABLE II                                    __________________________________________________________________________    Strength of Orthopedic Bandages Prepared                                      With Multiply-substituted Amino Ether Compounds                                ##STR5##                                                                                           Catalyst Level:                                                               5 mole %                                                                              10 mol %                                                              Strength at:                                            Example                                                                            R.sup.9                                                                          R.sup.1                                                                           R.sup.3                                                                          R.sup.6                                                                           R.sup.8                                                                          71/2 min                                                                          30 min                                                                            71/2 min                                                                          30 min                                      __________________________________________________________________________    E    H  Me  Me H   H  4.2 17.8                                                                              8.3 21.2                                        2    Me Me  Me H   H  6.4 20.9                                                                              10.0                                                                              24.1                                        F    Et Me  Me H   H  4.9 19.6                                                                              9.0 21.8                                        G    H  H   H  Me  Me 4.2 17.8                                                                              8.3 21.2                                        3    Me H   H  Me  Me 5.9 19.4                                                                              9.9 22.0                                        H    Et H   H  Me  Me 3.5 18.1                                                                              7.6 19.8                                        I    H  Me  Me Me  Me 1.9 16.1                                                                              7.0 18.6                                        4    Me Me  Me Me  Me 6.2 20.8                                                                              10.5                                                                              24.2                                        J    Et Me  Me Me  Me 3.4 16.9                                                                              8.5 19.7                                        __________________________________________________________________________     ("Me" is CH.sub.3 and "Et" is C.sub.2 H.sub.5)                           

The results shown in Table II, above, illustrate that the substitutionof the amino ether compounds of this invention with methyl groups on themorpholinyl rings does not defeat the relative general superiority ofthose compounds over the corresponding compounds having hydrogen orethyl at the R⁹ position.

Example 6 and Comparative Examples K, L and M

A contemporaneously prepared and tested series of Examples prepared andtested as in the preceding Examples gave the results shown in Table III.

                  TABLE III                                                       ______________________________________                                        Strength of Contemporaneously Prepared and Tested                             Orthopedic Bandages                                                            ##STR6##                                                                                    Catalyst Level                                                                5 mole %  10 mole %                                            Exam-                Strength at:                                             ple   R.sup.9 R.sup.10                                                                              R.sup.11                                                                           71/2 min                                                                            30 min                                                                              71/2 min                                                                            30 min                           ______________________________________                                        K     H       H       H    3.8   16.8  7.4   19.3                             6     CH.sub.3                                                                              H       H    8.5   18.7  --    --                               L     H       CH.sub.3                                                                              H    4.7   17.0  10.0  20.6                             M     CH.sub.3                                                                              H       CH.sub.3                                                                           2.3   16.7  6.8   17.6                             ______________________________________                                    

The results in Table III illustrate that an alpha-methyl substitutedamino ether compound of this invention yields casts which possess earlystrength superior to casts prepared with similar compounds wherein: (1)R⁹ is hydrogen and is hydrogen, (2) R⁹ is hydrogen and is methyl and (3)R⁹ and R¹¹ are methyl.

Adhesive Formulations Examples 7 and 8 and Comparative Examples N, P andQ

An isocyanate-functional prepolymer was prepared by combining 315 parts4,4'-diphenylmethane diisocyanate and 400 parts "LHT 28" polyol (a 6000M.W. triol containing secondary hydroxyl groups, commercially availablefrom Union Carbide Corporation) in a closed reaction vessel equippedwith a stirrer and a nitrogen atmosphere. The resulting mixture washeated to 60° C. to melt the diisocyanate. Next, 1000 parts Polymeg™2000 polyol (a 2000 M.W. diol having primary hydroxyl groups,commercially available from Quaker Oats Co.) was heated to 60° C. andadded to the reaction vessel, followed by addition of 66 parts "HB-40"plasticizer (a partially hydrogenated terphenyl, commercially availablefrom Monsanto Corp.). After addition of all ingredients, the reactionmixture was maintained at 60° C. for 4 hours with stirring undernitrogen. The resulting prepolymer was cooled to 40° C. and stored in asealed container under nitrogen.

To 535 parts of the above prepolymer were added 10 parts Cab-O-Sil M5™fumed silica (commercially available from Cabot Corp.), 30 partstoluene, 200 parts Regal™ 300R furnace carbon black (commerciallyavailable from Cabot Corp.), 25 parts Mesamoll™ plasticizer(alkylsulphonic ester of phenol, commercially available from MobayChemical Corp.), 112 parts of terpene-phenolic resin Piccofyn A-135available from Hercules Inc. and the amount of the catalysts shown inTable IV. These ingredients were stirred under nitrogen until a uniformmixture was obtained. The resulting mixture was stored in a sealedcontainer.

In a reaction vessel equipped with a stirrer, reflux condenser and anitrogen atmosphere were combined 1610 parts Desmodur N-75™ (biuret ofhexamethylene diisocyanate commercially available from Mobay ChemicalCo.), 427 parts "A-189" gamma-mercaptopropyltrimethoxy silane, and 1.3parts dimethylpiperazine. The mixture was stirred at 80° C. for twohours and cooled to room temperature. 35 Parts of the resulting silanecompound were mixed with the prepolymer/catalyst prepared above.

The rate of strength build up of each sealant was evaluated using the"Flatwise Tensile Test". A 6.4 mm wide×7.9 mm thick×101.6 mm long beadof sealant was laid centrally along the long axis of a 76.2 mm×152.4 mmglass panel, two 6.4 mm spacers were placed on the panel at each end ofthe bead, a second glass panel of the same dimensions was placed on topof the spacers, and the resulting assembly was invented and allowed tocure at 24° C. and 50% R.H. The tensile strength of the cured assemblywas evaluated using a "Thwing-Albert Intelect-2000" tensile testeroperated at a crosshead speed of 508 mm/minute. The following resultswere obtained using laminated safety glass panels. Unless otherwiseindicated, the mode of failure was cohesive, i.e. within the bond.

                  TABLE IV                                                        ______________________________________                                        Tensile Strength of Adhesives                                                            Catalyst                                                                             Tensile Strength (psi)                                                 Amount at                                                          Example                                                                              Catalyst  (pbw)    2.7 hr                                                                              5.5 hr                                                                              48 hr                                                                              7 days                             ______________________________________                                        N      DMDEE*    1.5      10    70    352  676                                P      DMDEE     3.0      39    103   423  808                                Q      DMDEE     3.0      24    92    335  658                                7      MEMPE*    1.5      29    97    578  847                                8      MEMPE     3.0      48    130   573  771                                ______________________________________                                         *DMDEE is 2,2dimorpholinyldiethyl ether                                       *MEMPE is 4[2-[1-methyl-2-(4-morpholinyl)ethoxy]ethyl]-morpholine        

What is claimed is:
 1. A compound having the formula: ##STR7## wherein:each of R¹ -R⁸ are individually hydrogen or lower alkyl; andR⁹ is amethyl group or phenyl group wherein the phenyl group may have one ormore lower alkyl substituents.
 2. A compound in accordance with claim 1wherein R¹ -R⁸ are hydrogen and R⁹ is methyl.
 3. A compound inaccordance with claim 1 wherein R¹ -R⁸ are hydrogen and R⁹ is phenyl. 4.A compound in accordance with claim 1 wherein R⁹ is methyl.
 5. Acompound in accordance with claim 1 wherein R⁹ is phenyl.
 6. A compoundin accordance with claim 1 wherein R¹ -R⁸ are hydrogen and methyl.
 7. Acompound in accordance with claim 1 wherein R¹ -R⁸ are hydrogen.